Darko Grncarov fooled the BBC into letting him appear as expert on Five Live

But Grncarov has been exposed as a prankster who used bogus social media accounts to make people believe he was a rising star in tennis, an investigation by US online magazine Slate revealed.

During the interview, Grncarov vowed to boycott the Australian Open if the name of the Margaret Court Arena was not changed because it is named after one of world’s greatest former players who is against same-sex marriage.

He told BBC Five Live: “If the name is still there, I’m not going to play.

“Even if it means I’m never going to be playing the tournament, I don’t care.”